I'm new within the past month to the game, but I've loved it so far and am looking to expand beyond the core set. I've read that you shouldn't buy later expansion packs without playing the earlier released ones b/c of progressive difficulty and rules...My question is: would it generally doable/wise to buy the Khazad-Dum expansion before playing the Shadows of Mirkwood adventure packs, being they're not full expansions? Essentially, is there anything earth-shattering/game-changing in those first six adventure packs that I should know/play before getting that first full expansion pack, Khazad-Dum?

In short I think you will find the card pool too shallow to beat any of the quests if you leap from Core to Khazad, but it might be possible. The first thing that comes to mind is the 2 cost eagles that are in the Mirkwood cycle - even now they tend to be in most of my tactics decks.

I would recommend first getting cards that's would help make a deck you would like to try out. You can worry about challenging the new quest a bit later. Of the two, though, I would recommend Shadows of Mirkwood first since most of the cards can easily work with deck building ideas already shown in the Core Set.

The adventure packs work in synergy with the deluxe expansion from which they come. Core + Mirkwood. Kazhad + adventure packs.... Not that you can't do it in any order you wish but the designers made the game in that sequence as well.

Thanks all. As intriguing as Khazad-Dum looks, I don't want to rush it and just make it a bad experience and it appears that's what would happen by the consensus here. I appreciate the links and advice.